The invention relates to an x-ray diagnostic installation for x-ray photographs comprising a program control device for the photographic cycle which contains an electronic read-only memory for each photographic program whose input is connected to a resettable pulse counter which is relayable step-by-step via a clock pulse generator and which memory delivers program signals predetermined by its program that correspond to the output signals of the pulse counter, wherein the outputs of all read-only memories are connected to the components they control via a program selector, and wherein, additionally to the read-only memories, a freely programmable memory for a freely programmable photographic program is provided.
In an x-ray diagnostic installation of this type, the program storage ensues purely electronically. It is not necessary to read mechanical program memories, for example data cards, for the program reproduction. Operational dependability, therefore, is great. For program selection, keys can be provided in a simple way. On the basis of the electronic memories for the photographic programs it is possible to conduct a program trial run, wherein for example the values and magnitudes respectively predetermined by the program are optically indicated.
In the subject of a prior German application No. P 26 47 928.7, for program storage a read-only memory is provided for fixed programs on the one hand and a freely programmable memory is provided on the other hand. In the freely programmable memory, a photographic program can be read in that can be composed completely in accord with the wishes of the user.
In practical application, there is the desire to be able to permanently retain such a freely composed program, so that it is available as required. The freely programmable memory is not suited for this, for various free programs are read into it and upon the read in of a free program its contents are erased.